Project on supercurrents in nanowire Josephson junctions

For the paper: "Supercurrent interference in few-mode nanowire Josephson junctions" by Kun Zuo, Vincent Mourik, Daniel B. Szombati, Bas Nijholt, David J. van Woerkom, Attila Geresdi, Jun Chen, Viacheslav P. Ostroukh, Anton R. Akhmerov, Sebastian R. Plissard, Diana Car, Erik P. A. M. Bakkers, Dmitry I. Pikulin, Leo P. Kouwenhoven, and Sergey M. Frolov.

Code written by Bas Nijholt, Viacheslav P. Ostroukh, Anton R. Akhmerov, and Dmitry I. Pikulin.

Files

This folder contains five Jupyter notebooks and three Python files:

• generate-data.ipynb
• explore-data.ipynb
• mean-free-path.ipynb
• paper-figures.ipynb
• example-toy-models.ipynb
• funcs.py
• common.py
• combine.py

Most of the functions used in generate-data.ipynb are defined in funcs.py.

All notebooks contain instructions of how it can be used.

generate-data.ipynb

Generates numerical data used in the paper.

mean-free-path.ipynb

Estimates the mean-free path using the data that is generated in generate-data.ipynb.

explore-data.ipynb

Interactively explore data files uploaded on the 4TU library. See for example current-phase relations for different system lengths, disorder strengths, with or without the spin-orbit or Zeeman effect, different temperatures, and more!

paper-figures.ipynb

Plot the figures that are found in the paper.

simple-example-toy-models.ipynb

Contains simple toy models and examples of how to calculate the current-phase relations.

Data

Download the data used in explore-data.ipynb and paper-figures.ipynb at http://doi.org/10.4121/uuid:daa83d96-85d6-4739-841e-52abc86b6b15 and put in in this folder as data/.

Installation (Windows/OS X/Linux)

• (Windows only) Install Windows Subsystem for Linux (WSL).

• (Windows only) Open "Bash on Ubuntu on Windows" and choose the Linux version of Miniconda in the next steps!

• Download miniconda for Python 3 and install it.

• (Windows only) Run the following command

echo 'export PATH="${HOME}/miniconda3/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

• Enter the directory with these downloaded files, with cd, for example:

cd ~/Downloads/supercurrent_data

• Then add a Python environment that contains all dependencies with:

conda env create -f environment.yml -n supercurrent

• To activate the environment that we just installed run:

source activate supercurrent

• Run jupyter-notebook in your terminal to open the *.ipynb files.

Alternative installation (only for the explore-data.ipynb notebook) (Windows/OS X/Linux)

If you do not have a working Python 3.6 environment:

• Download miniconda for Python 3.6 and install it.

If you already have conda do or just installed it, run:

conda env create -c conda-forge -n supercurrent python=3.6 holoviews=1.8 pandas pytables toolz numpy notebook
source activate supercurrent
jupyter notebook

If you already have a Python 3.6 environment without conda, use pip:

pip install -U holoviews==1.8.1 pandas tables toolz numpy notebook
jupyter notebook